NV_register: Non-volatile register
STTRAM: Spin Torque Transfer Random Access Memory
PCM: Phase Change Memory
RRAM: Resistive Random Access Memory
DRAM: Dynamic Random Access Memory, which is a memory widely used at present, wherein the information is lost after power loss, and in principle, it can endure unlimited read-write operations.
DIMM: Dual inline Memory Module, which is a slot for DRAM on main board.
PM: Persistent Memory, which is not easily lost and can be kept for long term. STTRAM, PCM and RRAM are all pertain to the PM, wherein the information is not lost after power is cutoff and can be searched byte-by-byte. However, the read-write endurance of PM is limited and the read-time and write-time are unbalanced. Depending on different materials, the time needed for writing on PM is 4-10 times that for reading from PM, and the read time of PM is one to four times slower than that of DRAM.
sys file system: used for checking and setting parameters of operating system kernel of a computer system, and capable of serving as a file management system of a uniform driver model.
ACPI: Advanced configuration and Power Interface Specification
BIOS: Basic Input Output System
SRAT: System Resource Affinity Table, a table in ACPI specification for describing the memory resource attributes.
Hot plug technology is a hot subject of system software technology in the computer system architecture field. The hot plug technology relates to plugging and removing various devices of a computer system without having to interrupt the power supply. The prior art has achieved hot plug (or hot plugging) of a central processing unit, hot plug of a DRAM, and hot plug of a vast majority of input-output devices. Currently, the hot plug technology provides a technological support for adjusting the resource utilization rate of a data center server, migrating a virtual machine, saving energy consumption and other aspects. Therefore, the high-efficient hot plug technology has a significant value in disaster recovery, scalability and flexibility of a server in a data center.
Recently, Persistent Memory (PM) develops rapidly. PM is gradually becoming an important supplement to or replacement for DRAM due to advantages, such as byte addressability, non-volatile performance, low energy consumption and high density. However, its development is limited by issues, such as asymmetric read-write times, slower read-write speeds compared to DRAM, limited use lifetimes, and consistency issues. With the progress of technology, some progress has been made with regard to these issues. However, how to perform hot plug of Persistent Memory has no complete and reliable solution. The present invention, focusing on hot plug problems of Persistent Memory, puts forward hot addition and hot removal methods and provides hot plug devices, addressing forth the hot plug problem.